MS4 Guidance

General MS4 Resources

• Description of Stormwater Structural Controls
• Guidance for the Management of Street Sweepings, Catch Basin and Stormwater System Sediments

Phase II MS4 Resources

• EPA Phase II MS4 Fact Sheets
• EPA Menu of BMPs for Stormwater
• Urbanized Area Map - 2010 US Census
• Urbanized Area Map - 2020 US Census

Phase I MS4 Resources

• MS4 Permit Resource Manual
• Phase I MS4 Monitoring Plan Guidance

Fertilizer Resources

• Florida-Friendly Fertilizer Model Ordinance
• Florida-Friendly Landscaping Model Ordinance
• BMPs for Golf Courses

Load Reduction Resources

• FSA MS4 Load Reduction Narrative
• FSA MS4 Load Reduction Assessment Tool
• FSA MS4 Load Reduction Final Report

TMDL Resources

MS4 permittees may be required to address impaired waterbodies (WBIDs) with Total Maximum Daily Loads (TMDLs) that the MS4 contributes to. There are multiple methods to address impaired waterbodies. 

• Some permittees are stakeholders in Basin Management Action Plans (BMAPs) which act as implementation plans for impaired waterbodies.
• Permittees may prioritize an impaired WBID via participation in a DEP-approved Reasonable Assurance Plan or Alternative Restoration Plan.
• If the impaired waterbody has one or more DEP-adopted / EPA-established TMDLs, the permittee must develop long-term implementation plans.
  1. Prioritize at least one WBID to address per permit cycle, and
  2. Develop an implementation plan to address the prioritized TMDL WBID. 

Prioritization Plan

1. Develop a list of WBIDs that have TMDLs. Resources: 
   Map of TMDL WBIDs and EPA established TMDLs.
   DEP adopted TMDLs, Adopted TMDL reports and Draft TMDL reports.
    
2. Review the MS4 Permit Resource Manual, pg. 74 on selecting and evaluating factors to prioritize TMDL waterbodies for implementation.
3. Select at least one TMDL WBID to address during the permit cycle (must not be a WBID that already has an approved/adopted implementation plan).
4. Submit TMDL Prioritization Plan to DEP for review/approval according to MS4 permit requirement. 

Monitoring

Some permittees may be required to develop monitoring and assessment plans to evaluate the contribution of the pollutant(s) of concern by the MS4, and load reductions achieved in relation to the TMDL Report.

Implementation Plan

Permittees that have prioritized a TMDL WBID must submit a TMDL Implementation Plan. The purpose of the plan is to address the impairment through implementation of additional BMPs in addition to their current SWMP activities. The plan may include: 

• a list of additional structural and/or non-structural BMPs and other planned activities to achieve reductions of the pollutant of concern,
• a schedule for such additional BMPs and a projected load reduction associated with each; and
• a long-term strategy to evaluate the waterbody status, and the effectiveness of implemented activities.

NPDES-MS4@FloridaDEP.gov